Hydroelectric barber chair



. April 21, 1925.

W. F. KOKEN h 4HYDROELECTRIZC BARBER CHAIR Filed Dec. 2.4, 1923 5 Sheets-Sheet l WTZVW @fig-1' vApril 21, 19.25.

1,534,790- w. F. KOKEN HYDROELECTRIG BARBER CHAIR Filed D. 24, 1923 5 Sheets-sheet 2 l IN VENTO/e Wa/sr F'. Koken.

April 21, 1925.

W. F. KOKEN HYDROELECTRIC BARBER CHAIR Filed Dec. 24, 1923 5 Sheets-Sheet 3 Il if J- E m .N E W I Wa/er F Ko en. BY www April 2l, 1925.

W. F. KvOKEN HYDROELECTHIC BARBER CHAIR Fledpec. 24,- 1923 5 Sheets-SheetA 4 April 2l, 1925.

W. F. KOKEN HYDROELECTRIC BARBER CHAIR Filed Deo. 24, 1923 5 Sheets-Sheet` 5 Patented Apr. 21, 1925.

WALTER F. KOKEN, OF ST. LOUIS, MISSOURI.

HYDROELECTRIC BARBER CHAIR.

Application filed December 24, 1923,

To all wiz-om z't may concern.'

Be it known that I, VALTER F. KOKEN, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Hydroelectric Barber Chairs, of which the following is a full, clear, and exact description, such as will enable others skilled in the artto which it appertains to make and use the same.

This invention relates to chairs of the type that are used by barbers, dentists and other specialists for supporting a person on whom the specialist is operating, and particularly chairs of the kind described in my pending application for patent, Serial No. 622,518, filed March 3, 1923, in which the adjustment of the various parts of the chair can be effected by one hand of the operator in charge of the chair, thereby overcoming the necessity of requiring the operator to manually release a retaining device with one hand and use the other hand to move the part or parts of the chair that are to be adjusted.

One object of my present invention is to provide a novel mechanism for controlling the circulation of the liquid used in chairs of the kind mentioned to actuate the pistons that effect the adjustment of the back and the seat of the chair.

Another object is to provide a novel mechanism for starting and stopping the motor that is used to operate the pump which circulates the liquid that operates the pistons Other objects and desirable features of my invention will be hereinafter pointed out.

My improved chair is similar in general design to the chair described in my said pending application for patent, in that it comprises a. vertically-movable seat that is adapted to be raised and lowered, and adjustable back that is adapted to be a-rranged in an upright position or an inclined position, mechanism for effecting the vertical movement of the seat and for moving the back relatively to the seat to change the position of the back, consisting of two separate and distinct cylinders equipped with pistons, a motor-driven pump for circulating a non-compressible liquid that acts on said pistons, and a controlling means for said mechanism and pump con- Serial No. 682,457.

structed in such a way that it can be actuated by one hand of the operator in charge of the chair, thus leaving the other hand of the operator free to manipulate an instrument that is being used in the work in which the operator is engaged. The controlling ,means oi' my present chair is diiferent, however, from the controlling means of the chair described in my said application, in that it consists of a plurality of mechanically-operated valves and a plurality of automatic check valves combined in such a way as to cause the operating liquid to be admitted to and exhausted from the cylinders when a governing element is moved from one position to a different position.

Figure l of the drawings is a vertical sectional view of a portion of my improved chair, showing the seat frame, the stem which carries said frame and the verticallydisposed socket or cylinder in which said stem is reciprocatingly mounted.

Figure 2 is a top plan perspective view, illustrating the housing in the seat frame and some of the elementsv that are arranged inside of said housing. e

Figure 3 illustrates the position of the valves and the governing element of the controlling mechanism when the back is being reclinedsaid igure comprising a top plan view and a vertical transverse sectional VlGV.

Figures 4, 5 and 6 are similar views, showing the valves and governing element of the controlling mechanism arranged to cause the back to move into its upright position, to cause the seat to move upwardly and to lcause the seat to move downwardly, respectively.

vFigure 7 is a diagrammatic view, showing how the motor and the switch in the motor circuit are electrically connected with the electric supply circuit.

Figure 8 is an enlarged vertical sectional view of the automatic check valves of the controlling mechanism that are associated with the reclining cylinder, said view being taken on the line 8-8 of the top plan view of Figure 3.

Figure 9 is a detail sectional view, taken on the line 9 9 of Figure 10.

Figure 10 is an enlarged vertical sectional view of the switch in the motor cirbers chair of the type that comprises a vertically-adjustable seat A, an adjustable back Bvthat can be arranged in an upright position, as sliowii in Figure 11, or an inclined position, as vshown in Figure l2, an apron 'C and arnis' D-conne`cted with the back B i suelta fni-annei" that they will Amove in unison with the back, a supporting base or 'standard Il provided with a vertically-disposed socket orcylinder Ffa's shown in Fig-` ure 1,-and a piston `or stem G in said socket V'connested at its tiliper end to the seat frame Il of the chair; ".Ilie seat- A of the 'chair is raised by pumping a non-compressible liqiidsiieh as oil into the lower end of the vsocket F in the Standard, so" as to force the cstein G upwardly, and said vseat is lowered permitting' the liquid to escape from the socket F. Any suitable kind oi' pump can beused for circulating the liquid that act-uates the Stem G of the chair, but I prefer to use a rotary pump I mounted on the seat frame' of thechair and operate said pump -by'an electric motor J which is also mounted on the "s'eatff'rame of the chair. The means that I` preferto use Jfor moving the back of the chair relatively to the 'seat consists oa Vho'1`"izontallydisposed cylinder K carried bythe seat frame and provided with fa piston that is operatively connected by a "piston rod l and a system of links 2, 3 andV 4 to the apron C of the chair in such a way that the outward movement of said piston causes the back, ai'ms'and apron of the chair to move' into the position shown in v Figure 12 and the inward movement of said piston causes said back, arms and apron to inov'e into the position shown in Figure" 11g. When it is' desired to recline the back of the chair the operator actuates a device which sets the pump" I in operation and also causes the operating medium to be supplied to the cylinder K in such a way that the pistonof said cylinderY will move out'- wardlyg and .when it is desired to restore the back to its normal upright position, the .operator 'actuates said device so as to cause the operating medium to move the piston in the rcylinder K in the' opposite direction. The vertical' movement of the seat of the chair. can also be 'effected by operating the device just referred to so as te cause the operatingmediunrto b'e admitted to or exhausted from the cylinder F in the standard ofthechair'in. which the stein G reciprocates. i

` inoperative (lontrollz'ag means.

The controlling means that governs the circulation of the operating medium consists of a number of automatic check valves, I

a number of mechanically-operated valves, and a governinglelement, preferably a rock l shaft`L,'mounted inthe seat frame I-I of the chair and proyided with an operating handle M and with means for opening the mechanically-operated valves when said shaft is moved into certain positions. The motor erative, and when saidhandleis Vactuated to bring the seat to rest or to bring the back to rest, the motor will stop automatically,

thereby enabling the adjustment of the various parts of the chair to be governed by one liandtof the operator. 'The chaire, is "equipped with a stem holdingV device for holdingthe` stem against rotary movement, which stein holding device is combined with the governing element L in such a way that it will be rendered Vinoperative autoinatr cally whenever said governing Velement is moved to effect vthe adjustment ofthe seat or the back of the chair and will be rendered operative automatically whenever said governing element is restored to its former position after the desired adjustment of the chair has been made. In order to securely liold the back and apron of the chair in adjusted position, a clamping device N is provided ,for coeoperating with the 'piston rod 1 of the reclining cylinder K, said clamping device N being so constructed and arranged that it will normally hld the pis ton rod l Vof the reclining cylinder against movement, but. will be released or rendered au'toniaticallyl whenever the governing` element is moved into certain positions- Y Valifs of controlling mechanism,

The valves of the controlling mechanism comprise four mechanically-operated valves 5, 6,. 7 and 8,- a double-check valve Of that is associated withV one end of the reclining cylinder K, a double check valve Pthat is associated with the opposite end of said reico lll)

cliningL cylinder and a single check valve 9 the stem of the valve S to open said valve. The various valves above referred to are mounted in a valve box, designated as an entirety by the reference character R, and provided with ports and passageways through which the operating medium circulates. The particular construction of said valve box is immaterial, so far as my invention is concerned, but one convenient way of constructing said valve box is to form it from a plurality of horizontally-disposed plates arranged in superimposed relation and provided with grooves, openings or cored portions that constitute the ports and passageways for the operating medium. As shown in Figures 3 to 6, inclusive, the valve box R is provided with a chamber 10 common to the three valves 5, 6 and 7 and an inlet duct 11 that leads to Said chamber from the discharge side of the pump l. The valves 5, 6 and 7 control outlet ducts 5b, b and 7' through which the operating medium escapes from the valve chamber 10 in the valve box R, the duct 5b leading to the double check valve O, as shown in Figure 3, the duct 6b leading to the double check valve P, as shown in Figure 4, and the duct 7b leading to the pipe through which the operating medium is conducted down into the cylinder F in the base of the chair. The double check valves O and P, previously referred to, are of the same design and of the construction illustrated in Figure 8. The valve O comprises a top valve 12 arranged in vertical alignment with a bottom valve 13, a spring 14 that exerts upward pressure on the bottom valve 13 and holds it normally seated and a depending portion 15 on the underside of the top valve 12 that exerts downward pressure on the bottom valve 13 and causes said bottom valve to open when the top valve 12 opens under the influence of the operating liquid escaping from the valve chamber 10 through the outlet duet 5b. The top valve 12 controls a duct 16 that leads to the rear end of the reclining cylinder K, and the bottom valve 13 controls a duct 17 that leads from the front end of said reclining cylinder. The two corresponding top and bottoni valves 12a and 13a of the double check valve P control a duet 16L that leads to the front end of the reclining cylinder K and a duct 17, respectively, that leads from the rear end of the reclining cylinder. The outlet duct 7b in the valve box that is associated with the valve 7 leads to a vertically-disposed pipe 18 in the stem C of the chair that projects downwardly through the lower end of the stem, as shown in Figure 5, and the mechanically-operated valve 8, previously referred to, controls a port in the valve box through which the operating liquid escapes into the sump from which the pump draws its supply of liquid. In the chair herein shown the hollow stem Gr constitutes the sump and the liquid is withdrawn from said sump through a vertically-disposed pipe 19 whose upper end communicates with a duct 20 in the valve box that leads to the intake of the pump. Preferably, the valve box R is arranged inside of a casing S in the seat frame H of the chair, and said valve box is provided on its exterior with outlet ports through which the operating medium can escape from eertain of the ducts in said valve box and enter the casing S, finally draining out of said casing into the hollow stem G of the chair, on the upper end of which the casing S is mounted, as shown in Figure 1.

1f it is desired to niove the back of the chair from its upright position, shown in Figure 11, into its reclined position, shown in Figure 12, the handle of the governing shaft L is moved into a certain position, which, for convenience, I will refer to as its reclining position, so as to start the pump and cause the cam frL on the shaft L to move the valve 5 into its open position, as shown in Figure 3. The pump I then causes the liquid in the hollow stem G of the chair to circulate upwardly through the pi pe 19 into the pump, then from the pump through the duct 11 into the valve chamber 10, and thence from said valve chamber through the duct 5b to the double check valve The liquid exerts pressure on the top valve 12 of the double check valve O in a direction to cause said top valve to open, and as said top valve moves downwardly, the projection 15 on the underside of same engages the bottom valve 13 and moves said bottom valve into its open position. As soon as said top and bottom valves 12 and 13 open the liquid in the duct 5b passes into the duct 15 that leads to the rear end of the reclining cylinder K, and the liquid in front of the piston in said recliningcylinder escapes through the duct 17 leading from the front. end of the reclining cylinder, past the bottom valve 13 which controls the duct 17, and thence through a port in the exterior of the valve box R, said escaping liquid entering the casing S that surrounds the valve box and finally draining from said casing back into the hollow stem G of the chair. The liquid that is admitted to the rear end of the reclining cylinder K causes the piston in said cylinder to move outwardly, and when the back B of the chair reaches its fully reclined position or any other position into which it is desired to adjust the back, the operator moves the handle M of the governing shaft L into its neutral position so as to permit the valve 5 to close, and thus cut oft' the supply of liquid to the rear end of the reclining cylinder, the switch that governs the motor circuit being so arranged that the pump I will stop as soon as the operator starts to move the handle M from its :Ulti

piston rod 1, as shown in Figures 3 and 4,

the movable jaw 22 being normally acted upon by a spring 23, shown in Figure 1, that causes theV jaws 21 and 22 to exert sufficient pressure on the piston rod 1 to hold I the back and apron of the chair in adjusted position. Various means maybe provided for moving the jaw 22 in a direction to release the piston rod 1 preparatory to opening the valve 5', but I prefer to Vequip the governing shaft L with a cam 24 that cooperates with an extension or arm on the j aw 22 to move said jaw away from the stationary aw 21 when the handle M is moved into its reclining position, as shown in V`Figure 3, and permit said jaws topclamp the piston rod 1 when said handle is moved back to neutral position.

If the operator fails to stop the pump and change the position of the governing shaft L so as to close the valver, after the back of the chair has reached its fully reclined position, theV liquid will continuev to circulate from the valve chamber 10, through the rear end portion of the reclining cylinder K and then escape from said cylinder through a lateral discharge orifice 25 in same back into the sump or hollow stem G of the chair, thereby preventing damage'or injury to the mechanism in the event the operator fails to stop the pump after the back has reached its fully reclined position. Y

To raise the back from its reclined position into its upright position the handle M of the governing shaft L is turned from its neutral position into a different position, which, yfor convenience, I will refer to as its straightening position,l which operationl causes the pump to start and also causes the cam 6a on the governing shaft L to open the valve 6, asshown in Figure 4. As soon as said valve 6 opens the liquid which is being forced into the valve chamber Y10 by the pump I will escape from said valve chamber through the duct 6b and exert pressure on the top valve 12@L of the double check valve P in a direction to open said top valve and also open the bottom valve 13u. As soon as said valves 12n and 13a open the liquid in the'duct 6* will pass the valve 12a and flow through the duct r16a into the front end of the cylinder K, thereby moving i the piston of said cylinder rearwardly and causing the liquid behind said piston to escape through the duct 17 a past the valve 18a, and thence back to the sump or hollow stem G of the chair, it being` of course understood that the movement of the handle M of the-governing shaft L into its straightening position causes the clamp N to be rendered inoperative so as to release the piston rod 1 ofthe reclining cylinder. After the back of the chair has reached its upright position or the position into which it is desired to adjust said back, the operator moves the handle back to its neutral7 position, thus causing the motor to stop and also causing the valve 6 to close. If the operator fails to stop the motor after the back has reached its vertical position, the liquid that is admitted to the front end portion of the cylinder K will escape 'Y through the lateral discharge orifice 25 leading from said cylinder, and thus prevent damage or injury to the mechanism.

To raise the seat of thel chair the operator moves the handle M of the governing shaft L into its raising position so as to set the pump I in operation and cause the cam 7d on the shaft L toV open the valve 7. The pump I will then cause the liquid in the hollow stem G of the chair to circulate upwardly from said stem through the pipe 19 and duct 2O in the valve box, through the pump, then through the valve chamber 10 andthen thru the duct 7b in the valve box that communicates with the vertically-disposed pipe 18 in the stem of the chair, down through which pipe 18 the liquid passes into the socket or Vcylinder F,as indicated by the arrows in Figure 5. The upward pressure which the liquid in the socket F` exerts on the lower end of the stem G causes said stem andthe seat frame to nuove V upwardly, and after the seat hasreachedthe desired elevation, the handle M is moved into its neutral position, vso as to stop the motor and thepump actuated by the motor and cause the valve 7 to close.` The single check valve 9, previously referred to, that is arranged in the duct 7 b which leads from the valve 7 prevents the liquid from'backing up through the pipe 18, thereby trapping the liquid in the socket or cylinder F and securely holding the seat frame of the chair inthe position into which it has been moved.

In order to prevent the mechanismof the chair from being damaged or injured in the event the operator fails to stop the pump and turn the governing shaft L into such a position as to close the valve 7 after the seat frame of the chair has reached its extreme upper-position, the socket or cylinder F' is provided with a by-pass 26, as shown in Figure 5, that establishes communication between the socket or cylinder F and the hollow stem G when said stem reaches the end of its upward stroke. Consequently, if the pump continues in operation after the seat has reachedits extreme upper position, the liquid will continue to circulate fromV the socket F up through the by-pass 26, upwardly through the pipe 19 to the duct 20 that leads to the'l intakek of the pumpV and then from the discharge side of the pumpY through the duct 11, valve chamber 10, duct 7 b and pipe 18 to the lower end of the socket F of the chair.

To lower the seat the operator turns the handle M of the governing shaft L into still another position, hereinafter referred to as its lowering position, so as to cause the valve 8 to open and permit the liquid in the socket F to pass upwardly through the pipe 18 and be discharged into the stem G by the downward pressure which said stem exerts on the liquid in the socket F, the stem continuing to move downwardly by gravity until it reaches the end of its downward stroke, or until the governing shaft L is :turned into such a position that the arm 8n thereon causes the valve 8 to close. At such times, namely, when the seat is being lowered, the. motor and pump are idle, as the weight or load imposed on the stem G of the chair by the seat frame and the occupant of the cha-ir is sufiicient to cause the liquid in the socket F to pass upwardly through the pipe 18 and be discharged into the hollow stem G, if the valve 8 is open.

Switch.

The switch that controls the circuit of the motor J is combined with the governing shaft L in such a way that the motor will be started and stopped automatically when the handle M on said shaft is moved into certain positions. In the form of my invention herein illustrated the controlling switch for the motor circuit comprises two contacts 30 arranged in the motor circuit, and a shiftable circuit-closing device 31 that is adapted to snap into engagement with said contacts in three different positions of the handle M. .As snown in Figures 1 and 10, the governing shaft L extends through a sleeve 32 on the casing S and the handle M that is rigidly connected to said shaft L is provided with a pivotally mounted catch or holding device 33 that rides upon a iange 34 on the sleeve 32. Said liange 34 is provided in its periphery with four notches, designated in Figure 9 by the reference characters z z and w. The notch a: is so arranged that it will receive the catch 33 when the handle M is in its neutral position, the notch y is adapted to receive said catch when said handle is in its reclining position, the notch c is adapted to receive said catch when the handle is in its straightening position and the notch fw is adapted to receive said catch when the handle is in its raising position. When the handle M is arranged in its lowering position the catch 33 will ride on Athe portion of the edge of the flange 34 at the left of the notch w. The contacts 30, previously referred to, preferably consist of two rings'of conducting material mounted on an insulating sleeve 35 that surrounds the sleeve 32, said rings 3() being equipped with three pairs of projections arranged in alignment with the notches y, .e and fw, previously referred to, and designated by the reference characters y', e and fw. When the catch 33 is positioned in the notch the circuit closing device 31 cannot engage the contacts 30, but when said catch is positioned in either the notch i the notch .e or the notch fw, the circuit closing device 31 can engage the proj ections on the contacts 30 that are associated with said notches. The catch 33 is pivotally mount-ed between two ears 36 on the hub of the handle M, and the circuit closing device 31 is pivotally mounted on a jointed, springactuated structure carried by the ears 36. As shown in Figure 10, the ears 36 are so arranged that they overhang the sleeve 32 in which the governing shaft L turns, thus forming a support for a link 37 that is pivotally mounted on said ears by a pintle 38. A second link 39, which is pivotally mounted on the pintle 38, is joined by a link 40 to the catch 33 and the circuit closing device 31 is arranged at the lower end of the link 41 which is pivotally connected at 42 to the link 37. The two links 37 and 39 are combined with springs 43 which are connected to cross pieces arranged at the outer ends of said links, and the free end of the link 39 is connected to the upper end of two springs 44 whose lower ends are connected to the. ears 36 on the hub of the handle M. Normally, the springs 44 exert a downward pull on the free end of the link 39, thus causing the link 40 which is interposed between the link 39 and the catch 33 to exert pressure on said catch in a direction tendin to hold it in engagement with the flange 34 on the Isleeve 32. At such times the springs 43 which join the free ends of the links 37 and 39 together are arranged below the pintle 38 that forms the axis of movement of the links 37 and 39, as shown in Figure 1. lVhen the catch 33 is positioned in the notch w in the flange of the sleeve 32, so as to hold the handle M in its neutral position, the circuit closing device 31 will be held out of engagement with the contact rings 30, due to the fact that said notch :v is not deep enough to permit the catch 33 to move downwardly far enough to cause the link 37 to assume such a position that the circuit closing device 31 will engage the contacts 30. lfVhen the catch 33 is arranged in either of the notches s, y or w, however, which notches are deeper than the neutral notch the catch 33 will occupy a lower position and the link 37 will occupy such a position that thecircuit closing device 31 can engage the projections on the contacts 30 that are associated with the particular notch in the flange 34 in which the catch 33 is then positioned. To move the handle M from one position to a different position, the operato-r presses downwardly on the hand piece 45 on said handle, thereby causing a plungervia in the handle to exert pressure on the catch 33 and move it upwardly outJ of engagement with 4the flange 34 of the sleeve 32, as shown held Aout of engagement with the contactk rings 30, but when the handle M reaches its new position, assuming that the-catch 33 is in alignment with one or the other or the hot-ches e, .y or w in the new position of the handle, the circuit closing device 81 will snap downwardly into engagement with the contact rings 80` as soon as the operator relieves-the downward pressure on the handle piece-.45, due of course, tothe act' that the springs 44 lcontract assooii as the plunger 45'v1 moves upwardly under the influence ot its actuating spring 46. From the foregoing Y it will be Aunderstood that in my improved chair the operator can control the movements of thev variousparts of vthe chair with.

one hand and can cause the seat to move upwardly or downwardly and -can cause the back to move into its reclinedVV position or upright position by simply changing the position ot the handle M on the governing shaft L, the switch that-controls the motor circuit being combined with the shaft that governs the mechanically-operated valves in such a way that the pump will start and.

stop automatically 4with the openingand closing of said valves.

Stem Zo @Icing device.

'lhestein locking device is similar to the stein lockingdevice or" the chair described in my pending Avimplication `previously reterred to and consists of a shoe T arranged on the inside of the stem and anactuating device for said shoe formed by a'wedge or expanding element Tthat is connected by a rod U with 'a crank arm 47 on the shaft L, said crank arin being so arranged that the shoe T will normally hold the stein against rotary movement, but will be rendered inoperative autoniatically, thus releasing 'the stem whenever the handle M is moved from its' neutral position into one of its various other positions. Y

- Electric conductors.

vlh'e conductors that supply electric current to the motor J are also preferably of plication and consist of two collectorV rings V arranged on the underside of the casing S in the seat frame of the chair and insulated from said casing, vertically-disposed bars V reciprocatingly mounted Vin the standardof the chair and arranged in sliding engagement with contacts V2 in the standard tol which electric supply wires V3 are` connected, the exposed Vportions ci' the conductor bars V being covered with insulating material ard each of said bars being providedat-'its upper end with a shoe or brush Vt equipped with a notch that receives .one of the collector rings V. A means of the construction above described for connecting the inotorwith the supply circuit permits the seat of the vchair to be raised/andV lowered and also revolved and there are no loose wiresjorV flexible conductors to interfere with the movements ot the operator around the chairor interfere withV the .adjustment of the various parts ot the chair. Y

Having Athus described my invention what I claim and desire to secure by Letters Patent is: Y Y

l. A chair provided with a seat, a back, an hydro-electric means for moving the seat vertically and for moving the back relatively to the seat, a locking device for holding the back in adjusted position, a governing Velement for controlling said hydroelectric means', and'means for rendering said locking device inoperative .automatically when said governing element is actuated to eiect Ya change in -tlie position of the back.

2. A chair provided with a seat, a back, an hydro-electric means for moving the seat vertically and for moving the back relatively to the seat, a locking device tor holding the back in adjusted position, a governing element for controlling said hydroelectric means, and means whereby said locking device will be' rendered inoperative automatically when said governing element is yactuated to ei'ect a change in the position or' the backv and will be rendered operative automatically when said governing element isv restored to neutral position.

3. A chairprovfided with a seat, a back, an hydro-electric means tor moving the scat vertically and for moving the back relatively to the seat, a manually-operable governing element for controlling said hydroelectric means, 'and a Vloc-king device for holding` the back. in adjusted position coinbined' with said'governing element in such a way that movement of said governing element into either one of two different positions `causes said lockingV deviceto become inoperative automatically and movement of said governing element back to its neutral position causes said locking device to become operative automatically.

4. A chair provided with a seat, a back, an hydraulic means for moving the back relatively to the seat to change the position of the back, a manually-operable governing element for controlling said means, and a mechanically-operated locking device for holding the back in adjusted position combined with said governing element and adapted to be rendered operative and inoperative automatically by the operation of said governing element.

5. A chair provided with a seat, a back, a piston for moving the back relatively to the seat, means for causing an operating medium to act on said piston, a device that co-operates with the rod of said piston to hold the back in adjusted position, a manually-operable governing element for controlling the operating medium, and a means operated by said governing element for automatically rendering said holding device inoperative.

6. In an adjustable chair of the kind described, a cylinder provided with a piston for effecting the movement of an adjustable element of the chair, a double check valve composed of two valves that control ducts which communicate with the opposite ends of said cylinder, and means tor causing both of said valves to open when an operating medium exerts pressure on one of said valves.

7. In a chair of the type described, a cylinder provided with a piston that is used to eiect the adjustment of one of the elements of the chair, a` double check valve composed of two valves that control ducts which communicate with the opposite ends of said cylinder, a mechanically-operated valve for causing an operating medium to act on one of said check valves to open same, and means for transmitting movement from said check valve to the other check'valve so as to cause the operating mediuin in one end of the cylinder to escape from same when the mechanically-operated valve is actuated to admit the operating medium to the other end of the cylinder.

V8. Ina chair of the type described, a cylinder equipped with a piston for effecting the movement of one of the adjustable elements of the chair, a double check valve composed of two valves arranged in such a way that the movement of one of said valves into its open position causes the other valve to open, ducts controlled by said valves and communicating with the opposite ends of said cylinder, and means for causing an operating medium to exert pressure on one of said valves to open same and thereafter enter said cylinder.

9. In a chair of the type described, a cylinder provided with a piston for effecting the adjustment of one of the elements of the chair, double check valves associated with hydraulic the opposite ends of said cylinder, each of said check valves being composed of one valve that controls a duct which communicates with one end of the cylinder and a separate valve which controls a duct that communicates with the opposite end of the cylinder, means under control of the operator in charge of the chair for causing an operating medium to act on either of said double check valves, and means for causing the two valves of each of said check valves to operate in unison.

l0. In a chair of the type described, a cylinder provided with a piston which is adapted to be actuated by an operating medium in said cylinder to effect the adjustment of one of the elements of the chair, a double check valve composed of two separate valves for retaining the operating medium in said cylinder on opposite sides of said piston, a spring that holds both or' said valves seated, and means for causing an operating medium from a source of supply to act on one of said valves so as to open both of said valves.

11. In a chair of the type described, a cylinder provided with a piston that is used to effect the movement of one of the adjustable elements of the chair, separate and distinct manually-controlled valves for governing the admission ot' an operating medium to both ends of said cylinder, and a double check valve associated with each end of said cylinder, each of said double check valves being composed of two valves combined in such a way that the movement of one of said valves into its open position, due to the pressure exerted on same by the operating medium from the source of supply, causes the other valve to open and thus permit the operating medium in the cylinder to escape therefrom.

l2. In a chair of the type described, a cylinder provided with a piston for moving one of the adjustable elements of the chair, double check valves associated with the opposite ends of said cylinder and each composed of two valves arranged in longitudinal alignment with each other and provided with co-operating portions that cause said valves to move in unison, said double check valves being so arranged that they trap the operating medium in the opposite ends ot' the cylinder, and separate and distinct mechanically-operated control valves, one of which control valves is adapted to be opened when it is desired to have the piston move in one direction and the other being adapted to be opened when it is desired to have the piston move in the opposite direction.

13. A chair provided with a back, ay seat, separate cylinders equipped with pistons for moving said back and seat, a valve boX provided with a chamber to which an operating medium under pressure is supplied, two

medium into said seat cylinder when it isV desiredV to have the seat move upwardly, con,- trol valves for governing the escape ofthe operating medium from `said chamber through said'ducts, and double check valves associated iviththe opposite ends of .the

back cylinder and each composed of vtivo valves, oneotl Which controls` a duct that communicates with one end 'of' the back cylinder and the other controlling a rduct which communicatesivith theoppos'ite end of the back cylinder. Y

14. Al chair provided with a seat, a back, cylinders'equipped -with pistonev for Inoving 'the'` seat vertically7 yand for moving tlie back relatively to the seat, separate control valves that are adapted tobe opened to ad mit an operating lmedium to said cylinders, double check valves associated with the op posite Vends'fof the" back cylinder and arranged so that they are .rendered operative by the press/ure of the operating medium being admitted to thebacx cylinder, a locking device Vfor holding the backk in adjusted posities, and e meuellyfvrerable sev-@r11- ing element for actuating said control valves and for causing said locking device to become operative and inoperative.

l5. A cha-ir provided v.with a seat, a back, a socket eptiipped` WithaI vertically-movable stem that carries the* seat a cylinder equipped with a piston 'for moving the back relatively tothe seat, separate control'valves for admitting an Aoperating medium to said socket to raise the seatand for permitting the operating medium to escape Jfrom said socket to lower the seat, separate control valves for admitting an operating medium to the opposite ends of said-cylinder to reeline the back and move the back into its Y upright position, a manually-operable governing element for actua-tingv said control valves, and automatic double f check valves associated With the opposite ends of said cylinder and arranged so that they are rendered operative by. opening the control valves Which govern the admission of the operating medium to said cylinder.

16. A chair'providcd with a. seat, a back, a socket lequipped with Va vertically-movable stem that carries the seat, a cylinder equipped with a piston for movingthe back relatively to the seat, separate control valves it'or admitting an operating medium to said socket to raisethe seat and yfor permitting the operating mediumfto esca-pe from said socket to -lovver the seat, `separate control valves for admitting an operating Y medium to the opposite ends of said cylinder to reclinethe back and move'the back into its upright position, a manuallyfoperfV able governing element for actuating said control valves. automatic check valves associated with the opposite ends of said cylinder and arranged so that they are rendered operative by opening the control valves which govern the admission of the operat-` ing medium to said cylinder, and a locking device for holding the back in adjusted po! sition arranged so that it Will be rendered operative and inoperative by said governing element.

17. A chair provided with a seat, a back, a socket equipped with a vertically-movable stem that carries the seat, aV cylinder equipped with a piston vfor moving theback relatively to the seat, separate control valves for admitting an operating` medium to said socket to raise the seat and `for permitting the operating medium to escape Vfrom saidV socket to lower the seat, separate control valves for admitting an operating medium to the opposite Vends oi' said cylinder to recline the back and move the back into its upright position, a manually-operable gov.

carries the seat, a cylinder equipped .with a piston `for moving the backrrelatively to the seat, a. pump for circulating an operating medium that is used to actuate said stem and piston, a valve box equipped With ducts and passageivays through which the operating medium is admitted to and discharged from said socket and cylinder, control valves for governing the circulation oi lthe operating medium, and a casing surrounding said valve box that is adaptedf to receive the operating medium discharged from said valve box and conduct saidoperating medium into the hollow stein of the cha-ir. i

x19. A chair provided With a seat, a back, asocket, a hollow stem in said socket that carries the seat, a casing at the upper end of said stem whose interior:communicates with the interior of the stem, a cylinder equipped with a piston for moving the back relatively to the seat,v a pump'for circulatingan operating medium that is used to actuate said stem and piston, a valve box in said casing .provided .on its interior with ducts and passagevvaysthrough Which said operating medium circulates and on its exe terrier with Per-ts threilsh which the Operating medium escapes into said casing, and control valves in said valve box tor governing the circulation of the operating medium.

20. A chair provided with a seat that is adapted to be raised and lowered, a back that is adapted to be moved into a reclincd position and into an upright position, a socket equipped with a stem tor moving the seat vertically, a. cylinder equipped with a piston for moving the back relatively to the seat, a pump for circulating an operating medium that is used to actuate said stem and piston, separate control valves for said operating medium, one of which is adapted to be actuated to lower the seat, another to raise the seat, another to recline the back and another' to move the back into its vertical position, a manually-operable governing i leans tor actuating said valves, automatic check valves associated with the back cylinder and arranged so that they will be actuated by the operating medium admitted to said cylinder, and a locking device for holding the back in adjusted position controlled by said governing element.

2l. A chair provided with a seat, a socket, a hollow stem in said socket that carries said seat, a pump' for circulating an operating medium that is used to raise said stem, a valve box provided with ducts and passageways through which said operating medium circulates, two separate control valves in the valve box, one ot which is adapted to be opened to admit the operating medium to the socket and the other adapted to be opened to permit the operating medium to pass from the socket into the stem, and a manually-operable governing shaft in said valve box provided with means for opening said valves.

22. chair provided with a seat, a back, a socket, a. hollow stem in said socket that carries the seat, a casing at the uper end ot said stem arranged inside of the seat frame and communicating with the interior of the stein, a cylinder inside ot said casing provided with a piston for moving the back relatively to the seat, a pump for circulating an operating medium that is used to actuate'said stem and piston, a valve box having inernal ducts and passageways through which the operating medium circulates and external ports through which the operating medium can escape into said casing, control valves and check valves for governing the adniission and exhaust of the operating medium to and from the socket and to and trom the cylinder, and a manually-operable governing element on the seat trame provided with means for actuating said control valves.

Q3. A chair provided with a seat. a back, a socket, a hollow stem in said socket that carries the seat, a casing at the upper end of said stem arranged inside of the seat frame and communicating with the interior of the stem. a cylinder inside ot said casing provided with a piston for moving the back relatively to the seat, a pump tor circulating an operating medium that is used to actuate said stern and piston, a valve boi: having internal ducts and passageways through vhich the operating medium circulates and external ports through which the operating medium can escape into said casing, control valves and check valves for governing the admission and exhaust of the operating medium to and from the Socket and to and trom the cylinder, a manually-operable governing element on the seat trame provided with means t'or actuating the control valves, a spring-actuated clamp that coperates with the piston of said cylinder to hold the back in adjusted position, and means for rendering said clamp inoperative when said governing` element is moved into certain positions.

2a. A chair provided with a seat that is adapted to be raised and lowered, a back that is adapted to be reclined and straightened, a pump tor circulating an operating medium that is used to move the seat and to move the back relatively to the seat, Valves for controlling said operating medimn`r an electric motor tor driving` said pump. a manually-operable governing element for actuating said control valves, said governing element having a handle that is adapted to be moved into a plurality ot diliierent positions, and a switch -for the motor circuit comprising a circuit closing device and a retaining device for the handle of the governing element combined in such a way that movement of said retaining device into its inoperative posit-ion causes said circuit closing device to become inoperative.

95. A chair provided with an adjustable seat, an adjustable back, an operating means lor moving the seat and for moving the back relatively to the seat comprising an electric motor, a manually-operable governing element ior said operating means that is adapted to be moved into a plurality of differentpositions, a retaining device tor said governing element, a switch for the motor circuit provided with a movable circuit closing device, and a resilient means combined with said retaining device and said circuit closing device in such a way that said circuit closing device will be moved with a snap action out ot' engagement with its co-operat-ing contacts when said retaining` device is rendered inoperative and will move with a snap like action into engagement with its co-operating contacts when said retaining `Cevice becomes operative.

26. A chair providtd with a seat that is adapted to be raised and lowered, a back that is adapted to be reclined and straightened, a governing shaft for controlling the adjustment of the seat and back provided With 'an operating handle7 an electric inctor forming part of the ineans that is used to adjust the seat and the back, a retaining device on said handle, a stationaij7 part that co-operates with said retaining device toV hold the handle in adjusted position, a Switch for the motor circuit comprising a Vinovahle circuit closing device, a jointed structure that connects said circuit closing device with the retaining` device on the handle, and springs that exert pressure en saidjointed structure in such a manner as to cause the circuit closing device to snap out oi engagement with its co-operat-ing con- Vtactsivlien the said retaining` device is rendered inoperative and cause said circuit closing, device to snap intorengagenient with its co-operating contacts when said retaining device is rendered operative. Y

'2T- In an'adjustable chair of the type described, a manually-operable governing shaft,- a handle onsaid shaft that is adapted 113.0 circuit Vclosing device, a spring-actuated,

rjointed structure on said handle that carries said circuit closing device, a linl; that connects said glointed structure to said retaining device, a resilient ineans that nornially exerts pressure on said retaining device in a direction to hold it in engagement With the stationary part with Which it co-operates, and a vinanually-operable ineans for disengaging the retaining device roin said part.

28. In a chair of the type described, a manually-operable governing shaftprovided with a handle, a pivotally-niounted retaining device on said handle, a stationar7 part with which said retaining device cc-operates to hold the handle in adjusted position, ineans Y on said handle for disengaging said retaining device roin said stationary part, ears on said handle, two linksl pivotally inounted on said ears on a coininon pintle, springs connected to said links in sucha Way as to iiornially hold thein in an angular 'position -with relation to each other, a circuit closingV device pivotally connected to one of said linlrs, nieans 'tor connecting the other link to said retaining device, and a resilient ineans that exerts pressure on said retaining device in a direct-ion to torce it towards said stationary part.

Waarna r. nonna. 

